JP4380068B2 - Data reproduction device and editing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data reproducing device and an editing device, and more particularly to a data reproducing device for continuously reproducing data compression-encoded by a compression encoding method such as MPEG (Moving Picture Experts Group) and a data editing device for editing.
[0002]
[Prior art]
Conventionally, MPEG is widely known as a method for compressing and encoding information signals such as image information and audio information. An outline of this MPEG will be described. MPEG is the name of an organization that examines video coding standards established in 1988 by ISO / IEC JTC1 / SC2 (International Organization for Standardization / International Electrotechnical Standards Meeting Technical Committee 1 / Technical Committee 2, now SC29). Abbreviation for Moving Pictures Experts Group.
[0003]
MPEG includes MPEG1, MPEG2 and other standards. MPEG1 (MPEG Phase 1) is a standard for storage media of about 1.5 Mbps, and JPEG for the purpose of encoding still images and low transfer rates for video conferencing and videophones for integrated services digital network (ISDN). H. for video compression It inherits the basic technology of H.261 (CCITT SGXV, standardized by the current ITU-T SG15), and introduces a new technology for storage media. These were established in August 1993 as ISO / IEC 11172. In addition, MPEG2 (MPEG Phase 2) is a general-purpose standard that can be used for various applications such as communication and broadcasting, in November 1994, ISO / IEC 13818, H.264. It is established as 262.
[0004]
The encoded part of MPEG is created by combining several technologies. FIG. 9 is a block diagram showing an example of an MPEG image compression encoding apparatus. In the figure, the input image is decoded by the motion compensated predictor 21, and the time redundant portion is reduced by taking the difference between the motion compensated predicted image and the input image by the subtraction circuit 22. There are three modes of prediction from the past and the future. In addition, these can be switched and used for every 16 pixels or 16 pixels MB (macroblock). The prediction direction is determined by the picture type given to the input image. There are P picture, B picture, and I picture. There are two modes in which the prediction from the past and the MB are independently encoded without prediction, and the P picture is present. In addition, there are four modes in which prediction from the future, prediction from the past, prediction from both, and four modes independently encoded exist. It is the I picture that all MBs are encoded independently.
[0005]
In motion compensation (MC), a motion region is subjected to pattern matching for each MB to detect a motion vector with half-pel accuracy, and is predicted after being shifted by the amount of motion. The motion vector has a horizontal direction and a vertical direction, and is transmitted as additional information of the MB together with the MC mode indicating where the prediction is from. A group from an I picture to a picture before the next I picture is called a GOP (Group Of Picture), and when it is used in a storage medium or the like, generally about 15 pictures are used.
[0006]
The differential image signal extracted from the subtracting circuit 22 is subjected to orthogonal transformation in the DCT unit 23. Discrete cosine transform (DCT) is an orthogonal transform that discretely transforms an integral transform with a cosine function as an integral kernel into a finite space. In MPEG, two-dimensional DCT is performed on an 8 × 8 DCT block obtained by dividing MB into four. In general, a video signal has many low-frequency components and few high-frequency components. Therefore, when DCT is performed, coefficients are concentrated in a low frequency.
[0007]
The quantized image data (DCT coefficient) subjected to DCT is quantized by the quantizer 24. This quantization is based on a value obtained by multiplying a value obtained by weighting an 8 × 8 two-dimensional frequency called a quantization matrix with a visual characteristic and a value called a quantization scale for multiplying the whole by a scalar value. Divide by the digitized value. When inverse quantization is performed by the decoder, a value approximating the original DCT coefficient is obtained by multiplying by the quantized value.
[0008]
The quantized data is variable length encoded by the VLC unit 25. Of the quantized values, the direct current (DC) component uses DPCM (Differential Pulse Code Modulation) which is one of predictive coding. Also, AC (AC) components are zigzag scanned from low to high, with zero run length and effective coefficient value as one event, and Huffman coding that assigns codes with a short code length from those with high appearance probability Is done. The variable-length encoded data is stored in the temporary buffer 26 and output as encoded data at a predetermined transfer rate.
[0009]
The generated code amount for each macroblock of the output data is supplied to the code amount controller 27, and the error code amount with respect to the generated code amount with respect to the target code amount is fed back to the quantizer 24 to quantize the scale. The amount of code is controlled by adjusting. The quantized image data is inversely quantized by the inverse quantizer 28 and inversely DCTed by the inverse DCT unit 29, and then temporarily stored in the image memory 11 through the adder circuit 30, and then in the motion compensated predictor 21. , Used as a reference decoded image for calculating a difference image. The output signal of the motion compensation predictor 21 is input to the subtraction circuit 22 and the addition circuit 30.
[0010]
In the case of video, the encoded bit stream output from the buffer 26 has a variable amount of code for each picture. This is because MPEG uses information conversion such as DCT, quantization, and Huffman coding, and at the same time, it is necessary to adaptively change the code amount allocated to each picture in order to improve image quality. This is because the motion compensated prediction is performed, so that the entropy of the encoded image itself changes greatly, such as encoding the input image as it is in some cases and encoding a difference image that is the difference between the predicted images in some cases.
[0011]
In this case, in many cases, the code amount is controlled while allocating the entropy ratio of the image and keeping the limitation of the buffer. The limitation of this buffer is to encode the buffer on the decoding device side so that neither overflow nor underflow occurs, and it is specified as VBV (Video Buffering Verifier) in MPEG. Details of this are described in ISO-11172-2 and ISO13818-2 by the International Organization for Standardization (ISO). If this rule is observed, the rate in the VBV buffer changes locally, but if the observation time is increased, the transfer rate becomes a fixed transfer rate. In MPEG, this is defined as the fixed transfer rate.
[0012]
FIG. 10 is a block diagram showing an example of an apparatus for decoding encoded data compressed and encoded by MPEG. In the figure, encoded data compressed and encoded by MPEG is subjected to variable length decoding by a VLD unit 35 and then multiplied by a quantization width by an inverse quantizer 36 to obtain a value approximating the original DCT coefficient. Then, the signal is supplied to the inverse DCT unit 37 and subjected to inverse DCT to be locally decoded.
[0013]
Also, the motion vector and the prediction mode extracted from the inverse quantizer 36 are supplied to the motion compensated predictor 38 together with the decoded data from the image memory 40, thereby outputting the image data subjected to motion compensation prediction. An adder 39 decodes image data equivalent to the image data input to the encoding device by adding the data from the inverse DCT device 37 and the image data subjected to motion compensation prediction from the motion compensation predictor 38. The decoded data is supplied to the image memory 40 while being output to the outside.
[0014]
Conventionally, when editing compressed data such as MPEG data recorded on a recording medium, in order to maintain the continuity of the MPEG data, the generated code is such that the accumulated code amount of the VBV buffer is always fixed at the editing point. There is known a method of performing encoding in consideration of continuity, such as controlling the amount or encoding a GOP (Group of Picture) composed of a plurality of pictures as a unit of random access as a closed GOP (Japanese Patent Laid-Open 11-74799). Note that a closed GOP has a bit at the head of the GOP that indicates that it is limited to predicting only from the I picture of the current GOP in order to prevent problems with the reproduced image after editing. A state in which the bit is “1”.
[0015]
In addition, the encoded data is not subjected to any restrictions, and information indicating the data extracted as the editing material in the partial section of the encoded data and the information regarding the reproduction order are described, and the recorded code An editing apparatus that can realize video editing on a single recording medium without changing the digitized data has been proposed (Japanese Patent Laid-Open No. 11-187354).
[0016]
Further, in an editing apparatus that edits the first moving image and the second moving image at a predetermined editing point, an editing apparatus that uses two decoders to synchronize and reproduce two output image data at the editing point. Is also known conventionally (Japanese Patent Laid-Open No. 9-214877).
[0017]
[Problems to be solved by the invention]
Among the conventional devices described above, in the conventional device described in Japanese Patent Laid-Open No. 11-74799, the generated code amount is controlled so that the VBV buffer is always fixed for each GOP so that it can be edited anywhere. Since encoding restrictions are taken into consideration, such as encoding a GOP as a closed GOP, there is a problem that the encoding efficiency decreases.
[0018]
Further, in the conventional apparatus described in Japanese Patent Laid-Open No. 11-187354, playback is displayed as if it was edited, but the continuity at the editing point is incomplete, such as initialization of the decoder buffer for MPEG data. Temporary stillness may occur.
[0019]
Furthermore, in the conventional apparatus described in Japanese Patent Application Laid-Open No. 9-214877, the concept of using two decoders is described, but information on which decoder plays back recorded data, and waits. The description for realization such as the operation of the decoder is not clear.
[0020]
The present invention has been made in view of the above points, and an object of the present invention is to provide a data reproducing apparatus and an editing apparatus capable of improving the encoded image quality.
[0021]
Another object of the present invention is to provide an editing apparatus that can perform high-quality editing and can prepare at the next editing point at high speed.
[0022]
[Means for Solving the Problems]
  In order to achieve the above object, the data reproducing apparatus of the present invention defines the encoded data that can be continuously reproduced encoded and generated in one recording unit as a cell,A responsible decoder number indicating which one of the plurality of decoders is decoded by each of the plurality of cells or divided cells, decoding start information indicating the start of decoding of each cell or each divided cell, and each cell Or display start information indicating the display start of each divided cell, display stop information indicating the display stop of each cell or each divided cell, and reproduction order information indicating the reproduction order of each cell or each divided cell.Based on the data reading means for reading the reproduction control information from the recording medium, a plurality of decoders for decoding the encoded data, and the reproduction control information output from the data reading means, two or more cells or one of the plurality of cells is selected. Input control means for inputting two or more divided cells obtained by dividing one cell into a plurality of decoders in a reproduction order, time information in decoded data output from the plurality of decoders, and reproduction output from the data reading means Based on the control information, the decoded data to be displayed is output from one of the plurality of decoders, and the decoded data of the cells is output from the plurality of decoders in the reproduction order specified by the reproduction control information. The decoder control means for controlling the operation of the plurality of decoders in order, and the decoded data to be displayed output from one of the plurality of decoders. Is obtained by a configuration having a selection means for.
[0023]
  In the present invention, even if the encoded data recorded on the recording medium is not edited and recorded, it can be edited and reproduced as if it had been edited. Therefore, excessive encoding is restricted for the purpose of maintaining continuity. Can be made unnecessary. In addition, since a plurality of decoders are used in order, a temporary stop for buffer initialization can be eliminated.Further, in the present invention, since the responsible information of the decoder is clarified by the reproduction control information, the standby decoder can be operated only to the minimum necessary operation.
[0025]
In order to achieve the above object, the data reproduction apparatus of the present invention causes the decoder control means to output the decoded data of the cells from a plurality of decoders in the reproduction order specified by the reproduction control information. In addition, when controlling the operation of a plurality of decoders in order, for the decoder waiting for decoding, the decoder waiting for decoding is determined based on the decoding start information for starting decoding next in the reproduction control information. Seek to the beginning of the GOP of the encoded data encoded by the MPEG method that constitutes the cell input to the picture, and then decode the picture necessary for decoding the picture corresponding to the display start point, and then display it. It is characterized in that the reproduction of the picture of the starting point to start is on standby in a state where it can be displayed in real time. In the present invention, it is possible to control the standby decoder so that it can be immediately reproduced.
[0026]
In order to achieve the above object, the data editing apparatus according to the present invention encodes a plurality of cells when encoded data that can be continuously reproduced and encoded and generated in one recording unit is defined as a cell. One cell or one divided cell obtained by dividing one cell into a plurality of cells based on the reproduction information by sequentially reproducing encoded data of a plurality of cells from a recording medium on which at least data is recorded Decoding start information indicating start of cell decoding, display start information indicating display start of one cell or one divided cell, display stop information indicating display stop of one cell or one divided cell, and a plurality of cells Or, reproduction control information indicating an arbitrary editing point, which includes reproduction order information indicating the reproduction order of a plurality of divided cells, and a responsible decoder number indicating which one of the plurality of decoders is used for decoding. Recording medium or other The encoded data and the reproduction control information of a plurality of cells are read from the recording means for recording on the recording medium, the recording medium, or the recording medium and the other recording medium, and read based on the read reproduction control information. A data reproduction device for sequentially selecting a plurality of decoders that decode encoded data of a plurality of cells and outputting decoded data to be displayed is provided.
[0027]
In the present invention, it is possible to arbitrarily edit and reproduce a plurality of cells by the data reproducing apparatus based on the reproduction control information corresponding to the editing point arbitrarily. Further, according to the present invention, editing and reproduction intended by the user can be performed only by recording the reproduction control information.
[0028]
Here, the data reproducing apparatus described above is connected to a cell read by the reading means and the editing / reproducing that connects the cells read by the reading means in an order different from the reading order based on the reproduction control information. Additional edit playback that adds another cell that is decoded before, after, or in the middle of the cell, and deletion that deletes only the part that is completed in the minimum editing unit of one cell from the cell read by the reading means At least one of the editing and playback is performed.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of an embodiment of a data reproducing apparatus according to the present invention. As shown in the figure, in this embodiment, two decoders, MPEG decoders 6 and 7, are provided. In the recording medium 1 to be reproduced in this embodiment, encoded data compressed and encoded by the MPEG system is recorded. In this encoded data, a plurality of continuous data groups are recorded as a collection of continuously reproducible data encoded and generated in one recording unit.
[0030]
In addition to the above-described encoded data, the recording medium 1 shows reproduction control information (decoding start information described later (for example, from the beginning of a continuous file) indicating how to reproduce these encoded data. Relative address), display start information (for example, start time indicated in the same format as the SCR time defined in MPEG), display stop information (for example, stop time indicated in the same format as the SCR time defined in MPEG), Decoder number in charge (for example, 1 and 2 if there are two decoders), reproduction order information (one piece of continuously reproducible encoded data such as one program information (this is referred to as continuous data in this specification) Or cell information), that is, cell information is recorded in the reproduction order))), for example, an area different from the encoded data recording area It is recorded.
[0031]
The reproduction control information is recorded by, for example, sequentially decoding encoded data recorded on the recording medium 1 and inputting an edit point desired by the user while viewing the obtained reproduction image. It can be changed.
[0032]
The encoded data and reproduction control information recorded on the recording medium 1 are read by the data reading unit 2. The read reproduction control information is supplied to the reproduction controller 3. The reproduction controller 3 extracts reproduction order information from the input reproduction control information, and the continuous data (cell) that is first decoded in the reproduction order to the data reading unit 2 based on the reproduction order information; Instruction information is output so as to read continuous data (cell) that is decoded second in the reproduction order.
[0033]
As a result, the data reading unit 2 supplies the first MPEG decoder 6 of the encoded data read from the recording medium 1 with continuous data (cell # 1) that is decoded first in the reproduction order. The second MPEG decoder 7 is supplied with continuous data (cell # 2) that is decoded second in the reproduction order. Also, the playback controller 3 sends the two MPEG decoders 6 and 7 to the decoder controller 4 and the decoder controller 5 based on the decoding start information, and decodes the MPEG decoders 6 and 7 at the decoding start position. Instruction information is issued so that
[0034]
The MPEG decoders 6 and 7 that have received the standby instruction information stand by at the decoding start position, and the decoder controller 4 first decodes the encoded data corresponding to the cell # 1 based on the reproduction order. 6 to start. The data decoded by the MPEG decoder 6 is input to the reproduction time observer 8. The reproduction time observer 8 observes the reproduction time of the decoded data (reproduced image) of the MPEG decoder 6 decoding the cell # 1, and is described in the display start information of the cell # 1 from the reproduction controller 3. When a certain time comes, a switching signal is output to the switching controller 10.
[0035]
As a result, the reproduction image switch 11 selectively outputs the decoded data (reproduction image) decoded by the MPEG decoder 6 input through the reproduction time observer 8 and starts display on a monitor (not shown).
[0036]
On the other hand, the decoder controller 5 outputs instruction information to the MPEG decoder 7 so as to start decoding of the cell # 2 simultaneously with the start of decoding of the cell # 1 based on the reproduction order. The MPEG decoder 7 starts decoding of the cell # 2 and at the same time pauses and waits until the display start time of the cell # 2. After the start of displaying the reproduction image of the cell # 1, the reproduction time observer 8 monitors whether or not the reproduction time has reached the time described in the reproduction stop information of the cell # 1 from the reproduction controller 3. When the playback stop time is reached, a playback start instruction signal is output to the decoder controller 5 and at the same time, a switching signal is output to the switching controller 10.
[0037]
Upon receiving the reproduction start instruction signal, the decoder controller 5 outputs a control signal for starting the decoding operation to the MPEG decoder 7 which is suspended and waiting until the display start time of the cell # 2. As a result, the decoded data (image data) of the cell # 2 starts to be output from the MPEG decoder 7 and is supplied to the reproduction image switch 11 through the reproduction time observer 9.
[0038]
Also, the reproduction image switch 11 that has received the switching signal switches the decoded image to be selected from the decoded data (reproduction image) from the MPEG decoder 6 to the decoded data (reproduction image) from the MPEG decoder 7. As a result, the decoded data (reproduced image) from the MPEG decoder 7 described in the assigned decoder number of the cell # 2 is selectively output from the reproduced image switch 11 and the display of the reproduced image of the cell # 2 is not shown. Started by monitor.
[0039]
Also, when there is the third reproduction sequential data (cell # 3), the decoder controller 4 starts decoding cell # 3 simultaneously with the start of decoding cell # 2 based on the reproduction order. Instruction information is output to the MPEG decoder 6. The MPEG decoder 6 starts decoding of the cell # 3 and at the same time pauses and waits until the display start time of the cell # 3.
[0040]
After starting the reproduction image display of the cell # 2, the reproduction time observer 9 monitors whether or not the reproduction time has reached the time described in the reproduction stop information of the cell # 2 from the reproduction controller 3. When the playback stop time is reached, a playback start instruction signal is output to the decoder controller 4 and simultaneously, a switching signal is output to the switching controller 10. As a result, the decoded data (reproduced image) from the MPEG decoder 6 described in the assigned decoder number of the cell # 3 is selected and output from the reproduced image switch 11, and the display of the reproduced image of the cell # 3 is not shown. Started by monitor. Hereinafter, the above operation is repeated alternately in units of continuous data (cells) for the fourth and subsequent continuous data.
[0041]
As described above, according to the present embodiment, the encoded data recorded on the recording medium 1 is edited and recorded in accordance with the reproduction control information recorded on the recording medium 1 by arbitrarily setting the editing points in advance by the user. Even without it, you can edit and play as if you were editing. Also, the user can set a number of the above edit points, perform various edits, and sometimes redo. Further, since the editing / reproduction intended by the user can be performed only by recording the reproduction control information, there is no inconvenience for the user, and the capacity of the recording medium 1 is only retained in the original encoded data recorded at the beginning. Therefore, waste of capacity can be prevented.
[0042]
Here, there are three patterns for editing and reproducing. Next, a method for reproducing the above three patterns of two continuous data will be described with reference to FIG. First, the first pattern is a pattern in which continuous data # 1 (cell # 1) and continuous data # 2 (cell # 2) are connected and reproduced continuously.
[0043]
In this first pattern, the assigned decoder number corresponding to cell # 1 is “1”, and there is a reproduction start time and a reproduction stop time. The assigned decoder number corresponding to the cell # 2 is “2”, and there are a reproduction start time and a reproduction stop time. As shown in FIG. 2A, switching is performed by synchronizing the playback stop time of the MPEG decoder 6 that decodes the cell # 1 with the playback start time of the MPEG decoder 7 that decodes the cell # 2. Switch.
[0044]
Next, the second pattern is a pattern in which additional continuous data # 2 is inserted into continuous data # 1. In the second pattern, as shown in FIG. 2B, the originally existing cell # 1 is decomposed (divided) into two cells # 1a and # 1b. The assigned decoder number corresponding to the cell # 1a is “1”, and there is a reproduction start time and a reproduction stop time. The assigned decoder number corresponding to the cell # 2 is “2”, and there are a reproduction start time and a reproduction stop time. The assigned decoder number corresponding to the cell # 1b is “1”, and there is a reproduction start time and a reproduction stop time.
[0045]
In this case, as shown in FIG. 2B, at the first switching point, the reproduction stop time of the MPEG decoder 6 that decodes the cell # 1a and the reproduction start time of the MPEG decoder 7 that decodes the cell # 2 Synchronize and switch the playback image. At the second switching point, the playback image is switched by synchronizing the playback stop time of the MPEG decoder 7 that decodes the cell # 2 and the playback start time of the MPEG decoder 6 that decodes the cell # 1b.
[0046]
Next, the third pattern is a pattern for erasing the middle of the continuous data # 1. In the third pattern, as shown in FIG. 2C, the continuous data # 1 that originally existed is decomposed (divided) into three cells # 1a, # 1b, and # 1c. Since the middle divided cell # 1b is erased, there are actually two cells # 1a and # 1c. In this case, the assigned decoder number corresponding to the divided cell # 1a is “1”, and there is a reproduction start time and a reproduction stop time. The assigned decoder number corresponding to the divided cell # 1c is “2”, and includes a reproduction start time and a reproduction stop time.
[0047]
As shown in FIG. 2C, the switching is performed by synchronizing the reproduction stop time corresponding to the MPEG decoder 6 that decodes the divided cell # 1a and the reproduction start time of the MPEG decoder 7 that decodes the divided cell # 1c. To switch the playback image. As shown in FIG. 2C, the start position of the reproduction stop position of the MPEG decoder 6 and the erased continuous data portion (# 1b) and the reproduction start position of the MPEG decoder 7 are erased. The end position of the continuous data portion (# 1b) is shifted, but even if it is said to be erased, MPEG can only be played back in GOP units, so erasing can only be done in GOP units. Since the start position of the specified erased continuous data portion is not necessarily in GOP units, this represents a state in which the GOP including the decoder 6 playback stop frame is not erased and is not erased. Because. Details of erasure will be described later.
[0048]
In the first and second patterns described above, the original continuous data recorded on the recording medium is not erased by editing. However, in the third pattern, a part of the original continuous data is erased. Is done. For example, if there is an unnecessary part such as a disliked scene or commercial image in one cell, the unnecessary part of the original continuous data (cell) is deleted by editing this third pattern, One original continuous data (cell) is rewritten into two continuous data (cells).
[0049]
Next, the operation of the decoder in the reproduction standby state will be described with reference to FIG. In FIG. 4 and FIG. 4 to be described later, I, P, and B are MPEG-defined I picture (intraframe encoded image), P picture (interframe forward prediction encoded image), and B picture (bidirectional predictive encoding). Image). The continuous data (cell) described above is composed of a plurality of GOPs, but the decoding start information describes a relative address from the head of the cell.
[0050]
As a typical example, it is assumed that the time as the decoding start information is the presentation time of the second P picture P2 in GOP4 shown in FIG. 3, for example. In this case, even if decoding is attempted from the picture P2, the picture P2 is an MPEG P picture, and image generation is impossible unless decoding is performed from the first I picture of the GOP. Therefore, the decoding start information is the start address of the GOP.
[0051]
Therefore, the position to which the relative address of the decoding start information points is the head of GOP4 in FIG. Upon receiving the standby instruction, the decoder 6 or 7 seeks to the head of GOP4, decodes the picture P2 from there, and waits in a state where the picture P2 can be displayed at any time.
[0052]
Next, a method for erasing the first half of the cell will be described with reference to FIG. Erasing does not erase the entire portion that is not displayed. For example, even if the user gives an instruction to erase the part before P2 in FIG. 4, if picture P2 is not decoded from the first I picture of GOP4, image generation is performed. Since it cannot, the GOP4 cannot be erased.
[0053]
Therefore, the parts to be actually erased are GOP1, GOP2, and GOP3, and GOP4 is not erased. If the display effective picture is displayed from P2, the playback standby point may be P2. That is, in this case, GOP4 is not erased, but is decoded from the beginning of GOP4 and reproduced and displayed from the portion of picture P2, so that the picture before P2 is displayed as if it was erased from the user's point of view.
[0054]
Next, a structural example of the reproduction control information used in the present invention will be described in detail with reference to FIG. As described above, the data of the reproduction control information is recorded on the recording medium, for example, in an area different from the recording area of the encoded data. In addition, the data structure of the reproduction control information is a structure described hierarchically as shown in FIGS. 5A to 5D as one file in a form compliant with the file system.
[0055]
As shown in FIGS. 5A and 5B, the number of playback programs is described in 1 byte in the first layer of the playback control information. Here, an information group describing a series of cell playback methods on a recording medium is defined as one program. The number of reproduction programs can define a maximum of 256 pieces of reproduction program information.
[0056]
In the reproduction program information, as shown in FIG. 5C, the number of reproduction cells is described with 1 byte, and the reproduction cell information is described with a fixed length for one cell. Up to 256 playback cell information can be defined for the number of playback cells. A cell indicates one piece of encoded data that can be reproduced continuously. For example, a file name is defined in a file system in a one-to-one correspondence with a cell number.
[0057]
As shown in FIG. 5D, the reproduction cell information includes a reproduction cell number of 2 bytes, decoding start information, that is, a relative address of 4 bytes from the beginning of the reproduction cell that can start decoding, reproduction start information, that is, a reproduction start time. The reproduction stop information, that is, the reproduction stop time is described by 6 bytes, the assigned decoder number 4 bits, and the standby status 4 bits, respectively.
[0058]
The reproduction start information and the reproduction stop information are described in a format as shown in FIG. This is in a form consistent with the description of PTS (Presentation Time Stamp) which is the time management information of the reproduction output of the multiplexing system of MPEG2. The PTS indicates a time stamp with respect to a system clock reference (SCR) value that is basically a clock of 90 kHz, and can be described at 27 MHz by using an extension portion when further accuracy is provided. It is made into the composition. Generally, since the compression-encoded data is multiplexed by the MPEG method, it is very easy to manage.
[0059]
Further, the assigned decoder number describes the number of the decoder and is 4 bits. Therefore, it is possible to describe the number of up to 15 decoders (number 0 is not used). Further, the 4-bit standby status indicates that when the value is “0”, the process ends there, and when the value is “1”, the next cell is ready for reproduction and waits. Other values are reserved.
[0060]
For example, cells # 1, # 2, and # 3 as shown in FIG. 8 are recorded on the recording medium, the respective decoding start address information is adrs1, adrs2, and adrs3, and the reproduction start time information is PTM1, PTM3, FIG. 7 shows a specific description example of the reproduction control information when PTM5 and reproduction stop time information are PTM2, PTM4, and PTM6.
[0061]
As shown in FIGS. 7A and 7B, the reproduction control information describes one piece of reproduction program information as a program to be reproduced in the order of cell # 1, cell # 2, and cell # 3. Of course, it is possible to configure any number of programs from the resources of the three cells by combining the three cells and specifying the part of the playback order.
[0062]
The reproduction cell information 1 shown in FIG. 7C is information of the cell # 1, and as shown in FIG. 7D, the decoding start information is adrs1, the reproduction start information is PTM1, the reproduction stop information is PTM2, and the responsible decoder. Since the number is “1” and the standby status is “1”, after the reproduction of the cell # 1 is stopped, the cell # 3 assigned to the next assigned decoder number “1” is prepared for reproduction and stands by. It will be.
[0063]
Also, the reproduction cell information 2 shown in FIG. 7C is information on cell # 2, and as shown in FIG. 7D, the decoding start information is adrs2, the reproduction start information is PTM3, and the reproduction stop information is PTM4. Since the decoder number is “2” and the standby status is “0”, there is no need to wait after the cell # 2 is stopped.
[0064]
Further, the reproduction cell information 3 shown in FIG. 7C is information on the cell # 3. As shown in FIG. 7D, the decoding start information is adrs3, the reproduction start information is PTM5, and the reproduction stop information is PTM6. Since the decoder number is “1”, after the reproduction of cell # 1 is stopped, the standby decoder performs decoding, and after the reproduction of cell # 3 is stopped, the standby status is “0”. So there is no need to wait.
[0065]
According to the present embodiment described above, the encoded data recorded on the recording medium 1 is not edited and recorded according to the reproduction control information recorded on the recording medium 1 by arbitrarily setting the editing points in advance by the user. However, since editing and reproduction can be performed as if they had been edited, it is not necessary to limit the encoding excessively for the purpose of maintaining continuity. Also, since the two MPEG decoders 6 and 7 are used alternately, there is no need to pause for buffer initialization, and the information assigned to the decoder is clarified in the playback control information. Therefore, the operation of the MPEG decoder in standby can be made only to the minimum necessary operation.
[0066]
The present invention is not limited to the above embodiment, and various other modifications can be applied. For example, the reproduction control information has been described as being recorded in a different area from the encoded data on the recording medium. However, the reproduction control information can also be recorded in the same area as the encoded data (such as a subcode area). is there.
[0067]
In addition, the description has been given on the assumption that the cells are all reproduced from the recording medium. For example, if there is a moving image file on the Internet and the file can always reproduce the same scene fixedly, the content It is also possible to edit with both of them mixed in the same manner as a cell on its own recording medium.
[0068]
Furthermore, although two MPEG decoders have been described in the above embodiment, three or more MPEG decoders may be used. For example, if there are complex edits that cannot be handled by two MPEG decoders, if two MPEG decoders attempt to seamlessly reproduce data, but take a long time due to a reset operation, etc., three MPEG decoders are used. In addition, when performing special effects (mix fade, multi-screen configuration, etc.), there is a possibility that four or more MPEG decoders may be used.
[0069]
Also, the encoded data and the reproduction control information may be recorded on the same recording medium or may be recorded on separate recording media. For example, the encoded data may be recorded on a hard disk or an optical disk, and the playback control information may be stored in a flash memory or a portable card memory, or another computer or hard disk connected to a wired or wireless network or a hard disk. It may be recorded on a recording medium of a device having a similar server function.
[0070]
【The invention's effect】
As described above, according to the present invention, continuity can be maintained by performing editing / playback as if it were edited without editing / recording the encoded data recorded on the recording medium. It is unnecessary to limit the encoding excessively for the purpose, and thus the image quality of the decoded data can be improved.
[0071]
In addition, according to the present invention, since a plurality of decoders are used in order, a pause for buffer initialization at an editing point is not necessary, so that high-quality editing can be performed.
[0072]
Furthermore, according to the present invention, the information in charge of the decoder is clarified by the reproduction control information, and the standby decoder is operated only to the minimum necessary operation, so that preparation for the next editing point is performed at high speed. be able to.
[0073]
Still further, according to the present invention, since the editing / reproduction intended by the user can be performed only by recording the reproduction control information, there is no inconvenience for the user, and the original encoded data in which the capacity of the recording medium 1 is first recorded Since it is only necessary to hold only the storage capacity, wasteful use of capacity can be prevented.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of a data reproducing apparatus of the present invention.
FIG. 2 is a diagram showing examples of reproduction patterns according to the present invention.
FIG. 3 is an explanatory diagram for explaining the operation of the decoder to the playback standby point according to the present invention.
FIG. 4 is an explanatory diagram for explaining the operation of a decoder when erasing a part of cells in the present invention.
FIG. 5 is a diagram showing a playback control information structure in the present invention.
FIG. 6 is a diagram illustrating a PTM information format example of display start information and display stop information of reproduction control information.
FIG. 7 is an explanatory diagram showing a specific example of reproduction control information according to the present invention.
FIG. 8 is an explanatory diagram of a cell corresponding to a specific example of reproduction control information in the present invention.
FIG. 9 is a block diagram of an example of an MPEG encoder.
FIG. 10 is a block diagram of an example of an MPEG decoder.
[Explanation of symbols]
1 Recording medium
2 Data reading part
3 Playback controller
4, 5 Decoder controller
6, 7 MPEG decoder
8, 9 Reproduction time observation device
10 Switching controller
11 Playback image switcher

Claims (4)

When coded data that can be continuously reproduced and encoded and generated in one recording unit is defined as a cell, it is determined which decoder among a plurality of decoders each of a plurality of cells or divided cells is decoded. Describes the assigned decoder number, the decoding start information indicating the start of decoding of each cell or each divided cell, the display start information indicating the display start of each cell or each divided cell, and the display stop of each cell or each divided cell Data reading means for reading from the recording medium reproduction control information including display stop information and reproduction order information indicating the reproduction order of each cell or each divided cell ;
A plurality of decoders for decoding the encoded data;
On the basis of the reproduction control information outputted from the data reading means, for inputting the reproduction order of two or more divided cells obtained by dividing the two or more cells or one cell of the plurality of cells to the plurality of decoders Input control means;
Decoding to be displayed from one of the plurality of decoders based on time information in decoded data output from the plurality of decoders and reproduction control information output from the data reading means Decoder control means for outputting data and controlling the operations of the plurality of decoders in order so that the decoded data of the cells are output from the plurality of decoders in the reproduction order specified by the reproduction control information When,
And a selection means for selecting decoded data to be displayed output from one of the plurality of decoders. The decoder control means performs decoding when sequentially controlling the operations of the plurality of decoders so that the decoded data of the cells are output from the plurality of decoders in a reproduction order specified by the reproduction control information. The decoder in standby is encoded by the MPEG system that constitutes the cell input to the decoder in standby for decoding based on the decoding start information to start decoding next in the reproduction control information. Seek to the beginning of the GOP of the encoded data, decode the picture necessary to decode the picture corresponding to the display start point, and display the playback of the picture at the start point to start display next in real time 2. The data reproducing apparatus according to claim 1 , wherein the data reproducing apparatus is in a standby state. When encoded data that can be continuously reproduced and encoded and generated in one recording unit is defined as a cell, the encoded data of the plurality of cells is recorded from a recording medium on which encoded data consisting of a plurality of cells is recorded. Are sequentially reproduced, and based on the reproduction information, one cell or one cell is divided into a plurality of divided cells, and decoding start information indicating decoding start of one divided cell, and the one cell or one cell. Display start information indicating display start of the divided cells, display stop information indicating display stop of the one cell or one divided cell, and reproduction order information indicating the reproduction order of the plurality of cells or the plurality of divided cells; A recording means for recording reproduction control information indicating an arbitrary editing point on the recording medium or other recording medium, comprising a responsible decoder number indicating which one of the plurality of decoders is used for decoding. ,
Read the encoded data and reproduction control information of the plurality of cells from the recording medium or from the recording medium and the other recording medium, and read the codes of the plurality of cells based on the read reproduction control information A data reproduction device for sequentially selecting a plurality of decoders for decoding the encoded data and outputting decoded data to be displayed, and editing the plurality of cells by the data reproduction device based on the reproduction control information A data editing apparatus for performing reproduction. The data reproduction apparatus is configured to edit and connect the cells read by the reading unit in an order different from the reading order based on the reproduction control information, and for the cells read by the reading unit, Additional editing / playback that adds another cell to be decoded before, after, or in the middle of the cell, and only the part that is completed in the minimum editing unit of any one cell with respect to the cell read by the reading means 4. The data editing apparatus according to claim 3 , wherein at least one of the deletion editing reproductions to be deleted is performed.

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